Synthetic Rutile

Natural rutile has many times the fire shown by diamond, but it is masked by the red, brown or black body colour. The black material has been used in mourning jewellery, but rutile is most usually seen as rich, reddish brown, needle-like inclusions within quartz or within other stones, where the rutile crystals create a star effect by reflecting light.

Igneous and metamorphic rocks and alluvial deposits in Australia, Brazil, USA, Italy, Mexico and Norway.

Synthetic Rutile Properties

Chemical Composition: 
Titanium Dioxide - TiO2
Classification / Type: 
The material is found abundant as inclusions (silk, needles, crystals, etc.) in number of gemstones preferably in quartz, tourmaline, ruby and sapphire but large facet table crystals are quite rare therefore gemological importance lies in the synthetic counterpart produced by flame fusion method.
Colors / Varieties: 
All colors, generally colorless with a yellow tinge.
Crystal System / Forms: 
Tetragonal System
Hardness: 
6 - 6.5
Specific Gravity: 
4.20
Cleavage / Fracture: 
Distinct
Optic Character: 
Anisotropic, D.R.; Uniaxial Positive
Lustre: 
Vitreous
Refractive Index / Birefringence: 
2.616 - 2.903 / 0.287
Pleochroism: 
Weak
Dispersion: 
0.290 (high fire)
Magnification: 
Generally clean, strong doubling giving a hazy appearance, dispersive fire
U.V. Fluorescence: 
Inert
Spectrum: 
Not diagnostic
Cause of Color: 
As per dopant used
Treatment (Enhancement): 
Dark colored boules of synthetic rutile are heated to give the light yellow color. Natural rutile is generally brown in color which is heated to give yellow color.
Specific Tests: 
Very high doubling and dispersive fire.
Synthesis: 
Flame Fusion Method
Simulants (with separation tests): 
G.G.G. (dispersion, doubling, S.G.), Y.A.G. (dispersion, doubling), Synthetic Cubic Zirconia (S.G., dispersion, doubling), Diamond (dispersion, doubling), Strontium Titanate (dispersion, doubling), Sphene (doubling, dispersion, inclusions), Zircon (dispersion, spectrum), etc.
Geological Occurrence: 
Natural rutile as inclusions in quartz, tourmaline and corundum. Synthetic rutile in a laboratory.
Cuts & Uses: 
Facetted cuts, etc.